Safety device



R' MATIN SAFETY DEVI C E Oct. 25,

3 Sheets-Sheet Filed Aug. 2, 1928 F I G- 4 5 -7 'Nm 'D KTTOR NEYS Oct. 25, 1932. R. MARTIN 1,884,785

SAFETY DEVIC E Filed Aug. 2, 1928 3 Sheets-Sheet 2 ROBERT MARTIN NvfNToR I TTORNEYS Oct. 25, 1932. R, MARTIN 1,884,785

SAFETY DEVICE Filed Aug.V 2, w28 s sheets-sheet 3 ROBERT Mmmm NVENTOR @f7/W TTORN ETS Patented Oct. 25, 1932 UNTED STATES PATENT orricr.

ROBERT MARTIN, OF SPONIDON, NEAR- DERBY, ENGLAND, ASSIGNOR TO CELANESE CORPORATON OF AMERICA, A CORPORATION OF DELAWARE SAFETY DEVICE Application led August 2, 1928, Serial No. 296,967, and in Great Britain August 13, 1927.

This invention relates to safety devices for machines or apparatus comprising one or more pairs of moving surfaces converging to form a nip, the object of the invention being to prevent accidents arising such by the operatives fingers or clothing being drawn in between the converging surfaces.

The pairs of converging surfaces may be formed for example by pairs of rolls, bowls in or cylinders. Such pairs of converging surfaces occur for instance in calendering machines for textile fabrics, rubber calendering machines, calendering rolls of paper making machines and other calendering machines and 3.5 apparatus and in biscuit manufacturers dough brakes, cloth stiff'ening and dressing mangles, dyers padding mangles, masticating roll machines for rubber, Celluloid or other plastic materials and generally in machines or apparatus in which materials are operated on by pressure in passing between rolls.

The object of the present invention is to provide such machines or apparatus with 25 safety devices which are rapid in action and will operate to stop the machine or apparatus in a very short time by eliminating the inertia of the driving mechanism. According to the invention machines or apparatus comprising one or more surfaces converging to form a nip or nips, and more particularly calendering machines, are provided with a safety device comprising one or more guard bars disposed in or near the entrance to the 3 nip or nips of the converging moving surfaces, a trigger device adapted to be released by a movement of the guard bar or bars either towards or away from the nip or nips, and

a declutching mechanism directly operated by the release of the trigger device to disconnect the driving mechanism of the machine or apparatus.

By these means, the danger of the converging surfaces continuing to move because of the inertia of the driving mechanism is avoided, and the stopping is practically instantaneous, while the stop motion is rendered effective either when the guard bar is moved towards the nip, as when fingers or clothing are caught in the nip, or when the guard bar is drawn away to expose the nip.

The declutching mechanism may conveniently comprise an arm or other member carried by a sleeve 1Keyed to or otherwise adapted to drive the first motion shaft of the ma-' chine, and a power-driven pulley mounted loose on the sleeve and carrying a movable member adapted to engage and to be disengaged from the arm or other member carried by the sleeve.

rEhe guard bar or bars, which should preferably entend the full length of the nip or nips, may be of any suitable shape, for eX- ample they may be triangular in cross sectien or of other shape approximating to the ferm of the converging surfaces, one of the bases of the triangle or like shape being arranged so that it faces outwards away from the nip of the rolls or other converging surfaces. For the best results, particularly in the case of a pair or pairs of cylindrical rolls, the guard bar or bars are disposed parallel to the nip or to the respective nips and are preferably so supported that parallelism is maintained when any part of the bar or of any of the bars is moved.

Furthermore where a plurality of guard bars are employed each disposed in or near the entrance to the nip of a pair of converging surfaces in a machine or apparatus comprising a plurality or series of pairs of converging surfaces, as for instance in the case of calendering or like machines having a series ef superposed rolls, the guard bars are preferably arranged in an interdependent manner so that a movement of any one of them brings about a corresponding movement in the others and also operates the stop motion.

Thus for example, in the case of a machine comprising a series of superposed horizontal rolls, the guard bar or bars may be mounted at their ends in parallel slides or guides, the ends of the bar or bars being connected by 9 reds to lever arms fixed to vertical spindles disposed at the right and left of the rolls, any movement of one end of a guard bar being transmitted by the consequent rotation of the corresponding vertical spindle at thatv vertical spindles, to the other end to the corresponding ends of any other guard bars and movement of the guard bar or bars at either end thereof being transmitted, by means of a link or rod connecting oppositely directed lever arms fixed on the vertical spindle and thereby to the other end of the guard bar or bars.

In the case of machines which are alternately run in opposite directions, as for instance dough brakes in which materials are passedv to and fro between a pair of rolls, the entrance to the nip is alternately on opposite sides of the rolls and accordingly, if

f desirable and convenient, a guard bar according to the present invention may be disposed in or near the entrance to the nip on each side of the machine.

The accompanying drawings illustrate one form of the invention as applied to a fourroll steam heated textile calendering machine of a well known type. As is known in such machines, the material travels successively round and between the rolls in a sinuous course, successive entrances to the nips being disposed alternately on opposite sides of the series of rolls.

Fig. 1 is a perspective view of the driving end of the calendering machine and shows a trigger release adapted to operate a declutching device.

Fig. 2 is a front elevation of the same end of the machine.

Fig. 3 is a vertical section of Fig. 2 looking in the direction of the arrow A and Fig. 4 is an enlarged detail view of the declutching device looking in the direction of the arrow B in Fig. 2.

Fig. 5 is a plan view of part of the machine, showing details of the operating means connected to the guard.

Fig. 6 is a detail of the trigger release, and

YFig. 7 is a sectional view of the co-acting members of the trigger release.

The drawings illustrate guard bars applied to each of the three intakes to the nips and since, as explained above, successive nip entrances are alternately on opposite sides of the series of rolls, the three guard bars are correspondingly disposed.

The guard bars l, preferablyof wood and of approximately triangular cross-section, are recessed at one of the vertices to receive steel bars 2 extending beyond the ends of the guard bars and having end's of square or rectangular cross-section grooved or slotted, as shown in Figures l2 and 3, to receive and slide upon the inwardlyy projecting webs of angle irons 3 secured at each side on the end frames 4 of the machine. The steel bars 2 in addition to sliding on the irons 3 are bored at each end to receive connecting rods 5, 6 which are adjustably secured thereto by means of nuts 7 the connecting rods 5, 6 being bent at their other ends so as to form short arms. At each end of the calendering machine is disposed a vertical spindle 8 capable of rotation in brackets 9 carried by the end frames 4. On each of the vertical spindles 8 are fixed three short levers 10 to receive the hooked ends of the connecting rods 5, 6. In all cases the levers 10 project from the vertical spindles 8 in the direction of the end frames 4 and are parallel to one another. Each of the spindles 8 carries a further lever 11 positioned at right angles to the levers 10, the lever 11 on the spindle 8 shown in Fig. l projecting outwards away from the rolls and the lever 11 on the other spindle 8 projecting towards the rolls. The two levers 11 are connected by a rod 12,'as clearly shown in 5. It will thus be seen that for any small rotation of the spindle 8 shown in Fig. 1 the other spindle 8 at the other end of the machine will rotate inthe opposite direction,

andy in consequence any backward or forward movement of a part of any one of the guard bars 1 results in a corresponding backward or forward' movement of all other parts of that bar andv also of the remaining guard bars 1, so that parallelism of the guard bars with respect to the rolls is maintained. The vertical spindle 8 at the driving end of the machine carries in addition as shown in Fig. 1 a trigger lever 13 with a flattened pin 14 at its end. The lever 13 is omitted from F ig. 5 to show the connection of the rod' 'with the lever 10. The lever 13 in its normal position is preferably positioned parallel to the rolls so that any displacement of the guard bars will produce a maximum displacement of the pin 14 in a direction perpendicular to the rolls. The pin 14 engages a second fiattened pin 15 at the end of a springbolt 16, which passes through the end frame 4 and carries atv its other end an anvil 17. Between the anvil 17 and the end frame a spiral spring 18 is placed round the springboltl.

A shaft arm 19 carried by a sleeve 20 keyed to the first motion shaft 21 of the machine transmits to the shaft 21 the power drive as hereinafter described. rlhe pulley 22 revolves on the sleeve 20, and to the inner side of its rim is fixed a bush 23 through which passes a pin 24 carrying at one endy a declutching lever 25 and at its other end' aboss 26 formed with a segmental projection 27 all) as shown in detail in 4. ABetween the boss 26 and the bush 23 and between the bush L 23 and the lever 25 spring washers 28 are disposed. The outer end of the shaft arm 19, as shown in Fig. 4, is adapted to engage or interlock with the segmental projection 27 when the latter is in the position shown in full lines in Fig. 4 but to clear it when in the position shown in dotted lines. A resilient member or keeper 29 fixed by screws 30 to the shaft arm 19 serves to keep the lati Cit ter in close engagement with the projection 27.

The dimensions of the pins 14, 15 will determine the amount of movement of the guard bars necessary to release the spring bolt and thereby stop the machine. Preferably the pins are of such a size that a rotation of the spindle 8 of about 4 5O will serve to disengage the pins, while the angle of the segmental projection 27 is such that a turning of the declutching lever 25 through about -90o serves to disengage the roj ection from the shaft arm 19. The flattened portions of the pins 14, 15 are shown at 14', 15 in Fig. 6, and the engagement of these flattened faces is also apparent in 7.

The operation of the device is as follows When the guard bars 1 are in their normal position the pin 14 is able to engage the pin 15 and thus hold the anvil 17 out of the path of the declutching lever 25. The latter, being arranged in radial position with respect to the pulley 22, causes the projection 27 to engage the arm 1S) .vherebytho powcrdrive is transmitted from the pulley 22 to the first motion shaft 20 of the machine. Any forward or backward motion of any of the guard bars 1 causes, through the connecting rods 5 or 6 and the levers 10, a rotation of the spindle 8 in one direction or the other, which rotation causes the pin 14 to move to one side or the other of the pin 15 as shown in Fig. 7, and immediately releases the springbolt 16, the spring 18 causing it to shoot outwards and thereby interpose the anvil 17 into the path of the declutching lever25. The latter on striking the anvil is rotated sufiiciently to disengage. the projection 27 from the shaft arm 19 and the pulley 22 thereafter acts as a loose pulley.

For the normal stopping of the machine en ordinary loose pulley 31 may be arranged coaXially with the pulley 22 and a belt fork 32 serves to transfer the belt from the pulley 22 to the pulley 31.

The particular form of the invention described above with reference to the drawings is purely illustrative of the invention and is in no way limitative in character.

lV hat l claim and desire t secure Letters Patent is 1. A machine comprising at least one pair of moving surfaces converging to form a nip, provided with a safety device comprising a guard bar disposed at the entrance to the nip, a trigger device adapted to be released either by a movement of the guard bar towards or by a movement away from the nip, and a declutching mechanism directly operated by the release of the trigger device to disconnect the driving mechanism of the machine.

2. A. machine comprising at least one pair of moving surfaces converging to form a nip, provided with a safety device comprising a guard bar disposed at the entrance to and parallel to the nip, a trigger device adapted to be released either by a movement of the guard bar towards or by a movement away from the nip, and a declutching mechanism directly operated by the release of the trigger device to disconnect the driving mechanism of the machine.

3. A machine comprising at least one pair of moving surfaces converging to form a nip, provided with a safety device compri g a guard bar disposed at the entrance to and parallel to the nip and adapted to maintain parallelism therewith when moved, a trigger device adapted to be released either by a movement of the guard bar towards or by a movement away from the nip, and a declutching mechanism directly operated by the release of the trigger device to disconnect the driving mechanism of the machine.

4. A machine comprising at least one pair of moving surfaces converging to form a nip, provided with a safety device comprising a guard bar disposed at the entrance to and parallel to the nip, a trigger device adapted to be released either by a movement of the guard bar towards or by a movement away from the nip, and a declutching mechanism directly operated by the release of the trigger device to disconnect the driving mechanism of the machine, spindles disposed opposite each end of the nip, oppositely directed levers fixed to said spindles, rods connecting said levers to the guard bar ends, and means comprising two further oppositely directed levers fined on the lspindles and al link connecting the said last-named levers, said means being adapted to cause the spindles to rotate in opposite directions, and thereby to move the rods connecting said first-named levers to the guard bar in the same direction to maintain the guard bar parallel to the nip.

5. A machine comprising at least one pair of moving surfaces converging to form a nip, provided with a safety/f device comprising a guard bar disposed at the entrance to the nip, a trigger device adapted to be released either by a movement of the guard bar towards or by a movement thereof away from the nip, and a declutching mechanism directly operated by the release of the trigger device and comprising a member carried by a sleeve adapted to drive the first motion shaft of the machine and a power driven pulley mounted loose on the sleeve and carrying a movable member adapted to engage and to be disengaged from the member carried by the sleeve.

6. A machine comprising at least one pair of moving surfaces converging to form a nip, provided with a safety device comprising a guard bar disposed at the entrance to and parallel to the nip and adapted to maintain parallelism therewith when moved, a trigger device adapted to be released either by a movement of the guard bar towardsxor by a movement thereof away from the nip, and a declutching mechanism directly operated by the release of the trigger device and comprising a member carried by a sleeve adapted to drive the first motion shaft of the machine and a power driven pulley mounted loose on the sleeve and 'carrying a movable member adapted to engage and to be disengaged from the member carried by the sleeve.

7. A calendering machine comprising at least one pair of rolls forming a nip, provided with a safety device comprising a guard bar disposed at the entrance to said nip, a trigger device adapted to be released either by a movement of the guard bar towards or by a movement away from the nip, and a declutching mechanism directly operated by the release of the trigger device to disconnect the driving mechanism of the machine.

8. A calendering machine comprising at least one pair ofrolls forming a nip, provided with a safety device comprising a guard bar disposed at the entrance to and parallel to said nip, a trigger device adapted to be released either by a movement of the guard bar towards or by a movement away from the nip, and a declutching mechanism directly operated by the release of the trigger device to disconnect the driving mechanism of the machine.

9. A calendering machine comprising at least one pair of rolls forming a nip, provided with a safety device comprisinga guard bar -z disposed at the entrance to and parallel to said nip and adapted to maintain parallelism therewith when moved, a trigger device adapted to be released either by a movement of the guard bar towards or by a movement away from the nip, and a declutching mechanism directly operated by thev release ofthe trigger device to disconnect the driving mechanism of the machine.

10. A calendering machine comprising at .least one pair of rolls forming a nip, provided with a safety device comprising a guard bar disposed at the entrance to and parallel to said nip, a trigger device adapted to be released either by a movement of the guard bar towards or by a movement away from the nip, and a declutching mechanism directly operated by the release of the trigger device to disconnect the driving mechanism of the machine, spindles disposed 0p- 'posite each end of the nip, oppositely didirection to maintain thev guard bar parallel to the nip.

l1. A calendering machine comprising at least one pair of rolls forming a nip, provided with a safety device comprisingl a guard bar disposed at the entrance to said nip", a trigger device adapted to be released both by a movement of the guard bar towards and by a movement thereof away from the nip, and a declutching mechanism directly operated by the vrelease of the trigger device and comprising a member carried by a sleeve adapted to drive the first motion shaft of the machine and a power driven pulley mounted loose on the sleeve and carrying a movable member adapted to engage and to be disengaged from the member carried by the sleeve.

12. A calendering machine comprising at least one pair of rolls forming a nip, provided with a safety device comprising a guard bar disposed at the entrance to and parallel to said nip and adapted to maintain parallelism there-with when moved, ay trigger device adapted to be released both by a movement of the guard bar towards and by a movement thereof away from the nip, and a declutching mechanism directly operated by the release of the trigger device and comprising a member carried by a sleeve adapted to drive the first motion shaft of the machine and a power driven pulley mounted loose on the sleeve and carrying a movable member adapted to engage and to be disengaged from the mem* ber carried by the sleeve.

In testimony whereof, I have hereunto subscribed my name.

ROBERT MARTIN.

Q." el. 

